Harman MPMi, Руководство пользователя

Страница: 40 / 54

40
USING YOUR MFXi/MPMi CONSOLE
The final output from your sound system can only ever be as good as the
weakest link in the chain, and especially important is the quality of the
source signal because this is the starting point of the chain. Just as you
need to become familiar with the control functions of your mixer, so you
must recognise the importance of correct choice of inputs, microphone
placement and input channel settings. However, no amount of careful
setting up can take account of the spontaneity and unpredictability of
live performance. The mixer must be set up to provide “spare” control
range to compensate for changing microphone position and the absorp-
tion effect of a large audience (different acoustic characteristics from
soundcheck to show).
MICROPHONE PLACEMENT
Careful microphone placement and the choice of a suitable type of
microphone for the job is one of the essentials of successful sound
reinforcement. The diagrams on the left show the different pick-up pat-
terns for the most common types of microphone. Cardioid microphones
are most sensitive to sound coming from in front, and hypercardioid
microphones offer even greater directivity, with a small amount of pickup
behind the microphone. These types are ideal for recording vocalists
or instruments, where rejection of unwanted sounds and elimination of
feedback is important. The aim should be to place the microphone as
close as physically possible to the source, to cut out unwanted surround-
ing sounds, allow a lower gain setting on the mixer and avoid feedback.
Also a well chosen and well placed microphone should not need any
appreciable equalisation.
There are no exact rules - let your ears be the judge. In the end, the
position that gives the desired effect is the correct position!
INITIAL SETUP
Once you have connected up your system (see the sections on connec-
tion and wiring earlier in this manual for guidance) you are ready to set
initial positions for the controls on your mixer.
Set up individual input channel as follows:
•
Connect your sources (microphone, keyboard etc.) to the required
inputs.
WARNING: Phantom powered mics should be connected before the
+48V is switched on. Ensure the PA system is OFF when switching
phantom power on or off.
• Set Master faders at 0, input faders at 0, and set power amplifier
levels to about 70%.
•
Provide a typical performance level signal and press the PFL button
on the first channel, monitoring the level on the bargraph meters.
•
Adjust the input gain until the meter display is in the amber section,
with occasional peaks to the first red LED at a typical maximum
source level. This allows sufficient headroom to accommodate
peaks and establishes the maximum level for normal operation
(but see note below).
•
Repeat this procedure on other channels as required. As more